1. Field of the Invention
The present invention relates to a color adjustment apparatus for adjusting a hue, saturation, and lightness (including luminance) of a selected hue range via a GUI (Graphical User Interface), an image forming apparatus, and a computer-readable recording medium having a color adjustment program.
2. Description of the Related Art
When a color image acquired by a camera is printed by an image forming apparatus, sometimes printing may be performed without color characteristics being properly corrected. Even if this color correction has been performed, there may be a desire to perform color adjustment on the image.
One method of adjusting color in such a case involves adjusting a hue, saturation, and lightness by converting image data from an RGB color system to image data of an HSV (Hue, Saturation, and Value) or HLS (Hue, Lightness, and Saturation) color system. This color adjustment method is performed by moving a knob of an adjustment slider for a respective one of a hue, saturation, and lightness after a hue range targeted for adjustment has been selected. In addition, an adjustment quantity (gain) relative to the quantity of a knob movement can also be adjusted.
Prior approaches do not effectively keep track of how the adjustment quantity of a respective one of a hue, saturation, and lightness changes in a selected hue range, in response to knob movement. In addition, even if such prior approaches allow gain to be adjusted, it is typically not possible to change the adjustment quantity in the selected hue range. Thus, in order to perform desired color adjustment under these approaches, color adjustment must be performed in a respective range where the hue range to be selected is finely divided.